Machine for thickening paper-pulp.



09F. POWERS.

MACHINE POP THIGKBNING PAPER PULP.

APPLICATION FILED JULY 12, 1911.

1,046, 1 O8;v`yy Patented Dee. 3, 1912.

'Be it known that I.,

CHARLES F. POWERS, OF THOMSON, NEW YORK.

' MACHINE FOR THICKENING PAPER-PULP.

Specification of Letters Patent.

Patented Dec. 3. 1912.

Application led July 12, 1.911.V Serial No. 638,099.

To all whom "tpmay concern:

CHARLES' F.- POWERS, a citizen of the United States, residing at T110mson,'county of Washington, Stateof New 'Yo'rk, have invented certain neviT and in Machines for and I do hereby declare the following to be a full, clear, and exact description of the invention, sucha's will enable' others skilled in the art to whichy itapp'ertains tov make and use the same.

The object of the invention is to produce an improved machine for thickening paper pulp, at times during the manufacture of paper when an undesirable quantity jof Water is present with the fiber, by removing5 apart of the Water from the excesslvelyf thinned pulp. Such a machine canV be used 'advantageously Vafter screening to thicken the stock before it. goes to the beaters, and is well adapted to recover the stock present in the White water, that is, the Water-from which the stock has been separated, but inwhich, nevertheless, a quantity of fine fiber is suspended, the loss' of which inthe long run is considerable.

Aupwardly through the screen upon- In accordance lwith the invention there 4is provided a rotatable conical stock collector comprisinga screen the truncated upper end of which is occupied by a circular vessel into which the White water or thin pulp is .directed from a pipe, and over the brim of.

which it quietly flows onto and down .the screen Vwhile the screen is rotated. The water. falls through the screen, and the fiber accumulatesupon and flows down and ofi' its surface. The meshes of the screenare kept clean by a stationary spray directed p a radial line froml top to bottom. The fiber, relieved from most of the Water by the screen finds its Way into a stock receptacle Which is preferably a pump Well.

I. have illustrated an embodiment of this invention in the machine pictured in the accompanying drawing in Which-V Figure l is a section on line l, l, of Fig. 2, which is a plan.

Referring to the drawing, the machinel is shown mounted upon a pump Well A into Which the thickened pulp is 'allowed to fall and from which it' may be pumped to a container or to apparatus in which it is next to be treated or manipulated. The base B of the .maehine proper which rests upon the Well A- is provided with an upturned peripheral curb L from which arms b eX- tend inwardly bridging au annular orifice c through which the thickened pulp is to flow into thefWell A. The arms b support a central .circular trough (Z which is to receive the water removed from the mixture and a- 'drain pipe e affords means of escape at all times for the Water collected in the trough d.

A step bearing f is provided in the center of the-bottom ofthe trough d for a vertical shaft' g, a second bearing/i for said shaft g'- being located in. an arched support v'- which is secured to and extends' upwardly from the tioor of. the trough (l. A circular vessel C is concentrically mounted fast on the shaft g above thebearing h and forms the hub of a conical -.screen frame which further com-A prises radially and downwardly extended spokes y' and aperipheral ring lc. A conical screen D is supported upon the screen frame extending from the brim of the vessel C to the peripheral ring 7c overhanging the annular orifice c in such a Way that ma- A stationary spray pipe o extends iip- -wardlv' through the trough (fand extends.

radially across the screen D, living close to its inner surface. This pipe 0 is perforated to project jets of Water outwardl31 thi-engin the screen to keep lthe wire faces of the screen clean and prevent them from becoming clogged. A valve-p is placed in the pipe 0 and serves as a means for -governing the spray therefrom.

In practice the diameter of the machine is usually about ten feet, and the screen is disposed at an angle of about 45 but both the diameter and the angle of the screen may lbe varied to meet the particular Aconditions under which the machiney is required to y work.

The operation, of vthe l device isv as follows: The screen is slowly rotated we will say at a speed 'of from six to twelve revol utions per minute witha machine of the size given above and a regular iow of the white water is established throughthe pipel into the vessel C. The white water iiows quietly over the brim of the vessel C onto the screen D gradually percolating through the screen vin its passage downwardly and leaving the fibers,'which were in suspension, `in a. thickcned pulp which `flows down and oft' the sur 'facego-f thescreen. lThe water which passes 'through the screen and 'which isf.freed of fiber collects in the trough d eventually 'draining oli' through the pipe e. The fibers are usually so ne that the ordinary passing ofthe white Water through alv fine screen' .is insufficient-to separate them from the liquid, as the rush of the, water through the meshes` will carry the fibers through even with' extremely fine mesh screens. Therefore, in addition'to the quiet overflow feed, I make use of' the centrifugal action of the rotating screen to counteract in a measure the action of gravity upon the liquid, so that its normal tendency to rush through 4.the screen apertures is correspond ingly diminished. This .permits the fineber to remain above the surface of the screen.l The film of liquid quietly overflow 'ing' the brim of the vessel Cin a thin sheet is constantly distributed over a wider area as 1t flows down the conicalsurface of the screen D. The flow' over the surface decreases, and the weight of the water is counteracted to a vconstantly increasing extent asv the lower edge of the screen is lapproached, and it is readily feasible to so regulate-the v speed and flow that practically all ofv the 1 =useful liber is recovered in the form of a rthicker pulp available. to be added to the 'A A main body 'of pulp in the stock-chest, while the waste water passing through the screenA D is substantially clear.

Having thus described my'invention what I claim 1s:

l. In a machine for separating water from paper stock, the combination ofa rotatablev screen having the formof a truncated cone l'and a feed vessel located within the trunf ,p cated end of said 'screen with its brim flush with said screen; substantiallyas described. 2. In a machine for separating 'water from vfibrous stock, the combinationof a rotatable screen .having thev form of an upright cone and' mounted to rotate uponitsl axis, and

means 'for feeding the stock-carrying water tially. as described. 6. Ina machine for separat-in onto said screen,` said means causing an overflow of said stock-carrying water onto the outer surface of said screen at a high point thereon without appreciable head whereby the pressure of the stock against the screen is minimized, substantially as described.

3. In a machine for separating Water from paper stock, ayrotatable stock collector come prising an upright conical screen mounted to rotate upon its aX1s, and a feed vessel located in the truncated upper end'of said. screen and adapted to. overflow onto said screen; substantially as described.

4. In a machine for separatingwater from paper stock, the combination of al rotatable .screen having the form of an upright cone mounted to rotate upon its'axis and'means for feeding. thestock carrying Water without-appreciable hydraulic head onto the surface of said screen adjacent its apex; substantially-l as described.

5. In a machine for separating water from paper's'tockf the combinationof a rotatable screen having the form of an upright truncated coue mounted to rotate upon its axis, a feed vessel occupying; the truncate upper end of and adapted to overflow'upon said screen, and a feed pipe discharging within f and below the brimof said vessel; substan y water from paper stock, the combination of arotatable screen having the form of an upright truncated cone mounted to rotate upon its axls,

a feed vessel occupying` the truncate upper end of said screen, a feed pipe discharging within and below the brim of said vessel, a drain trough underlying the base of said .screen to receive water passed through the- 8. In a machine for separating water from.

paper stock, the combination of a irotatable screen having the form of an upright truncated cone mounted to rotate upon its axis, a feed vessel occupying the truncate upper -end of said screen, and a stationary spray projector arranged radially acrossand adjacent the inner surface of said screen to direct aspray .through said screen; substantially as described. l 9. In amachine for separatin water fro paper stock, the combination o a rotatable screen having the form of an upright truncated cone mounted to `rotate upon its axis, a feed vessel. occupying the truncatel upper dinlly across und adjacent the inner surface of said screen to direct :i spray through seid screen substantially as described.

In testimony whereof I affix my sigimture, in presence of two Witnesses.

("IIARLES F. POWERS.

end of saidI screen, u feed pipe discharging within and belenv the brim of said vessel, a drain trough underlying the base of said screen to receive Water passed through the 1 screen, n pulp receptacle underlying the edge of said screen to receive the paper stock and i Witnesses:

:L stationary spray projector, arranged rw! E. SIMPSON,

Gmo. W. HUBBELL.

Copies of this patent may be obtained for five ,cents each, by addressing the Commissioner of Patents,

Wasrhingvtou, D. G. 

